Dictionary

# triangle

*noun*tri·an·gle \ˈtrī-ˌaŋ-gəl\

: a shape that is made up of three lines and three angles

: something that is shaped like a triangle

: a musical instrument that is made of a steel rod bent into the shape of a triangle and that you play by hitting with a metal rod

## Full Definition of *TRIANGLE*

1

**:**a polygon having three sides — compare spherical triangle

2

*a*

**:**a percussion instrument consisting of a rod of steel bent into the form of a triangle open at one angle and sounded by striking with a small metal rod

*b*

**:**a drafting instrument consisting of a thin flat right-angled triangle of wood or plastic with acute angles of 45 degrees or of 30 degrees and 60 degrees

3

**:**a situation in which one member of a couple is involved in a love affair with a third person

See triangle defined for English-language learners

See triangle defined for kids

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## Examples of *TRIANGLE*

- She cut the sandwiches into
*triangles*.

## Origin of *TRIANGLE*

Middle English, from Anglo-French, from Latin

*triangulum,*from neuter of*triangulus*triangular, from*tri-*+*angulus*angleFirst Known Use: 14th century

## Rhymes with *TRIANGLE*

TRIANGLES Defined for Kids

## triangle

*noun*tri·an·gle \ˈtrī-ˌaŋ-gəl\

## Definition of *TRIANGLE* for Kids

1

**:**a flat geometric figure that has three sides and three angles

2

**:**something that has three sides and three angles <a

*triangle*of land>

3

**:**a musical instrument made of a steel rod bent in the shape of a triangle with one open angle

Medical Dictionary

## triangle

*noun*tri·an·gle \ˈtrī-ˌaŋ-gəl\

## Medical Definition of *TRIANGLE *

**:**a three-sided region or space and especially an anatomical one—see anterior triangle, posterior triangle, scarpa's triangle, suboccipital triangle, superior carotid triangle

## Learn More About *TRIANGLE *

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triangle? Please tell us where you read or heard it (including the quote, if possible).